Socket for tube type incandescent lamps



May 29, 1951 R. P. ROSEN SOCKET FOR TUBE TYPE INCANDESCENT LAMPS 2 Sheets-Sheet 1 Filed May 20, 1949 INVENTOR. RUBEN P. Rosa! May 29, 1951 R. P. ROSEN SOCKET FUR TUBE TYPE INCANDESCENT LAMPS 2 Sheets-Sheet 2 Filed May 20, 1949 INVENTOR. RUBEN P. Rosin; if

Patented May 29, 1951 SOCKET FOR TUBE TYPE INCANDESCENT LAMPS Ruben P. Rosen, Philadelphia, Pa., assignor to Progress Manufacturing Company, Inc., Philadelphia, Pa., a corporation of Pennsylvania Application May 20, 1949, Serial No. 94,355

(01. ZOO-51.09)

2 Claims.

This invention relates generally to electrical lamp sockets and more particularly to an improved construction of an electrical socket designed to operatively receive the end of a tube type incandescent lamp.

Heretofore and prior to the present invention considerable dimculties have been encountered in connection with the removal and replacement of tube type incandescent lamps from and into their end-receiving sockets. The sockets r lamp-holders conventionally employed at the present time include special receptacles for removably receiving end caps which are snap-fitted on the metal ends of the tube lamp, and in order to remove a lamp from between such conventional holders it becomes necessary to also remove the end caps from their respective receptacles. Inasmuch as these end caps are snapfitted onto the ends of the lamp, it frequently occurs that they are inadverently discarded together with the burnt-out lamp, with the result that the lampholders, in the absence of such end caps, were rendered useless for receiving and holding the lamp operatively therebetween.

Among the principal objects of the present invention is the provision of a lampholder or socket for the end of a tube type incandescent lam in which all of the component parts thereof are arranged in the form of a single assembly, thereby avoiding the necessity of removing any com- :1,

ponent part for removal of the lamp therefrom and thus insuring against inadvertent loss of an essential part of the lamp holder.

Still another object of the present invention is to provide a lamp-holder of the character described having as a component part thereof a spring-biased socket for receiving one end of a tube type incandescent lamp, the socket being axially movable along the axis of the tubular lamp to an extent sufficient to free the opposite end of the lamp from its seating engagement with a relatively fixed socket mounted in spaced, coaxial alinement with the spring-biased movable socket.

Other objects and advantages of the present invention will appear more fully hereinafter, it being understood that the present invention consists substantially in the combination, construction, location and relative arrangement of parts, all as described in detail hereinafter, as shown in the accompanying drawings and as finally pointed out in the appended claims.

In the accompanying drawings, which are illustrative of a preferred form of the present invention,

Figure 1 is a perspective view of a lighting fixture showing a tube type incandescent lamp operatively supported between a pair of lamp-holders one of which is provided with a spring-biased socket part in accordance with the present invention;

Figure 2 is a perspective view, partially in section, of the relatively fixed uppermost socket or lamp-holder shown in Figure l Figure 3 is an exploded view showing in perspective the component parts of the assembly shown in Figure 2;

Figure 4 is a side elevational view of the aforesaid lamp-holder having the spring-biased socket part;

Figure 5 is an end elevational view thereof;

Figure 6 is a perspective view, partially in section, of the lamp-holder shown in Figures 4 and 5;

Figure 7 is an exploded view showing in perspective the component parts of the lamp-holder assembly of Figure 6; and

Figure 8 is a perspective view of the lower end portion of the movable socket part of said lampholder assembly of Figure 7.

Referring now more particularly to the drawings, it will be observed that the lamp holder of the present invention is adapted for use in a lighting fixture as shown in Figure 1, said lighting fixture having a main supporting base 10 designed for use in conjunction with a tube-type incandescent lamp H the opposite ends of which are respectively received by a pair of axial- 1y spaced socket parts !2 and I3, the socket part l2 being immovably fixed in position upon the supporting base H! of the lighting fixture, While the socket part l3 constitutes a relatively movable element of a lamp holder assembly, designated generally M, constructed in accordance with and embodying the principles of the present invention.

The relatively fixed socket part l2 essentially includes a main body part [5 suitably molded or otherwise formed of insulating material, said insulating body being provided therein with a socket l6 adapted to receive one of the ends of the tubular lamp H. The base of this socket H5 is fitted with a metal contact plate I! having a raised central portion l8 adapted to engage and make contact with the metal cap (not shown) conventionally fitted on each end of the lamp. The contact plate I! is so secured in the base of the lamp receiving socket 16, as by pins T -Il as to permanently engage an electrical contact element I9 extending laterally of the base of the socket l6, its outer end being adapted for securement by soldering or welding, as at 20, to an insulated conductor 2|, while its inner end is reversely turned, as at 22, for spring-pressed electrical engagement with the underside of the contact plate ll. The integrally formed supporting base 23 of the fixed socket I2 is provided in its rear face with a pair of interiorly threaded inserts 25 23 for respectively receiving a pair of securing screws 24 which are projected through suitable holes 25-25 formed in the supporting base of the lighting fixture. It will be understood that the socket part I2 is fixed to the mounting base of the fixture with the axis of its socket 16 extending lengthwise of the fixture, that is, coincident with the axis of the tube lamp adapted to be supported between the oppositely disposed socket parts i2 and E3.

The lamp holder i l, of which the socket part I3 forms a component element, includes a supporting back plate 25, preferably but not necessarily formed of metal, which back plate is adapted to be fixedly secured to the supporting base lil'oi the lighting fixture by a pair of screws 2'l-2l projected through openings 28 formed in the base I9 and into threaded apertures 2929 formed in the supporting back 23. This supporting back is provided along its opposite edges with channel-shaped guide ways 3939 and at its top with a horizontally disposed plate 3! terminating in a vertically disposed flange 32 extending between the forwardly disposed channel-forming flanges 3333. The horizontally disposed top plate 3| is'provided with a pair of laterally spaced struckout portions forming a pair of spring suspension hooks 3 %-3t from which are respectively suspended a pair of coiled tension springs 35-35.

Slidably associated with the supporting back 26 is a member 36 molded or otherwise suitably formed of insulating material, said portion being provided with a generally circular part 31 which is centrally recessed to provide a socket 38 for receiving one of the ends of the tubular lamp H, and with an integrally formed rear part 39 adapted to be slidably received within the channeled supporting back 26. It will be noted that the rear part 39 of the member 36 is generally of rectangular form, the opposite longitudinal edges it-d9 of which are respectively adapted for sliding fit within the channels 3il39 of the fixed member 25. It will be noted also thatthe upper end of the member 39 terminates in a plane spaced below that of the upper end of the socket 38 so that when the member 36 is slidably fitted within its support 29 and shifted therein to its uppermost position, the upper end of the back part 39 of the socketed member 35 is engaged by the lower edge of the depending flange 32 of the member 26 to thereby limit upward movement of the socketed part 36 relatively to its support 26.

Extending across the bottom end of the guided part 39 of the socketed member 36 is a plate 4| having a pair of laterally spaced hooks 4242 formed thereon, these hooks being extended upwardly through suitable openings 43 43 formed in the bottom end or" the part 39 for respective engagement by the lower ends of the coiled extension springs. These springs thus operate to draw the socketed part 36 upwardly within its channeled supporting member 26, the normal fixed position of the latter relatively to the fixed socket part l2 being such that when its associated socketed part 36 is drawn into its normal position by the springs 3535 the axially aligned sockets. l6, and 38 are relatively so spaced apart as to respectively embrace opposite ends of the tubular lamp ll. Thus, when it is desired to remove or replace the tubular lamp so normally received between the axially aligned socket parts 52 and I3, it only becomes necessary to shift the latter relatively to its fixed support 26 against the normal bias of the coiled springs 35-35 to thereby free the socket part i2 from the end of the tubular lamp received therein, the lamp being thereupon readily removed from between its supporting socketed holders.

It will be observed that whereas the relatively fixed socket part [2 is internally fitted with an unswitched contact element for electrically connecting the inserted end of the tubular lamp to the conductor 23 immediately upon insertion of the lamp end into the socket E5, the movable socket part It of the lamp holder assembly [4 is internally provided with a rotatable fixture switch as well as with an interlock switch which is operative to open the circuit to the lamp when the socket part it is retracted into lamp removing position. Thus, referring more particularly to Figures 6 and 7, it will be noted that the base of the socketed member 35 is centrally bored, as at 44, to receive a rotatable switch knob 45, the inner end of which is keried, as at 56, to receiv an S-shaped contact element ii. The opposite ends of this rotatable contact element 51 are respectively adapted to engage the arcuately shaped portions 48-43 of a pair of contact members 49 and 5E] fixed in the base of the socket 38, the member 50 being provided with a wing element 5| the free end of which is adapted to project upwardly through an opening 52 formed in an insulating plate 53 overlying the elements 59 and 58. fixed contact elements 59 and 59 are disposed in diametrically opposed relation within a suitable well 54 formed in the base of the socket 38. A metal contact plate 55 overlies the insulating plate 53 and is in electrical contact with the wing element 5| projecting upwardly through the open ing 52 in the intervening insulating plate 53. A plate 55 is centrally provided with a raised portion 56 adapted for contact by the metal cap (not shown) fitted on the end of the tube lamp. The several parts 45, 4?, 29, 5d, 53 and 55 are all secured in their fixed relation, as shown, within the base of the socket 99 by suitable securing elements, such as pins 5i-51 driven into the member 36 through suitably registering apertures in the members 53 and 55.

The member 49 is provided with a lateral extension terminating in a freely extending lip 58 projecting externally of the socket 38 through an opening 59 formed in the back wall portion thereof, said lip 58 being adapted to wipingly engage and make electrical contact with a brush type contact member 89 suitably staked to an insulator pad 6| fixedly secured in turn to the channeled support 26, the said pad 6| being se cured to the channeled support by rivets 52 or the like. A guard plate 63, also formed of insulating material, is disposed to the rear of the insulating pad 6| and is provided with an upper lip 64 which projects through a slot 65 formed in the insulating pad to extend across the top of the brush contact 69 to prevent accidental contact therewith. The brush contact 655 is connected, as by soldering or welding to the terminal end of an insulated conductor wire 65.

When the tubular lamp IE is mounted in position between its lamp holders l2 and Hi, as shown in Figure 1, the socketed part I3 of the lamp lhe arcuately shaped parts :33-t9 of these.

5 holder I4 is normally biased by the coil springs 35 into its upper lamp-engaging position and so holds the lamp securely between its axially aligned, opposed holders. In such condition of the lamp holder I4, the contact member 49 is in electrical engagement with the brush contact 60 (as see Figure 6). With the members 49 and 60 in contact with one another, the lamp may be turned on and off by rotation of the rotary switch element 41, the lamp being on when said switch element is in bridgin contact across the arcuate portions 4848 of the contact members 49 and 50.

When it is desired to remove or replace the lamp, the lamp and the socketed part I3 of the lamp holder I4 are together axially shifted against the biasing tension of the coil springs 35-35 into their full line position shown in Figure 4, whereupon the upper end of the lamp II is free to be swun outwardly of the relatively fixed lamp holder I2 and thence axially out of the relatively movable socketed part I3 of the lamp holder [4. Upon axially shifting the socketed part I3 of the lamp holder l4 into its lamp removing position, as shown in Figure 4, lip 58 of the contact member 49 is disengaged from the relatively fixed brush contact 60 in consequence of which the connection to the lamp is broken. If desired, and it is generally preferable so to do, the brush contact 69 is so arranged with respect to the lip 58 movable with the socketed part of the lamp holder I4 as to provide for breaking of the circuit tothe switch contact 49 when the socketed part is completely free of its lamp and is thus in its uppermost position. In such case, the lip 58 of the switch contact member 49 would be spaced above the brush contact 60, engagement with the brush contact being then normally made only when the socketed part of the lamp holder I4 is in lamp supporting position.

It will be understood, of course, that the present invention is susceptible of various changes and modifications which may be made from time to time without involving any departure from the general principles or real spirit thereof, and it is accordingly intended to claim the same broadly, as well as specifically, as indicated in the appended claims.

What is claimed as new and useful is:

1. A holder for a tubular incandescent lamp comprising, in combination, a fixed support for a lamp socket member, a lamp socket member slidably associated with said support for rectilinear movement relatively thereto along the longitudinal axis of the tubular lamp supported by said socket member, said socket member having an open-ended circular recess therein for receiving one end of said tubular lamp, a contact plate in the base of said lamp-receiving recess, a pair of spaced contact elements arranged beneath said plate with one of said elements in electrical contact therewith, a rotary switch element interposed between said spaced contact elements for opening and closing the electrical circuit therebetween, one of said contact elements including an extension projecting laterally of the socket with its outer end terminating short of said fixed support for the slidable socket member, and a brush contact element fixedly associated with said support and adapted to engage said terminal end of said laterally extended contact element to provide conjointly with the latter a safety interlock switch operative to close the circuit to said lamp socket contact plate oily when said lamp socket is in a predeterminedlyfixed position relative to its support.

2. In a holder for a tubular lamp as defined in claim 1, wherein said safety interlock switch is interposed between said slidable lamp socket and its support, said switch being opened or closed accordingly as said lamp socket is shifted relatively to its support.

RUBEN P. RO'SEN.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 2,306,908 Stifiel Dec. 29, 1942 2,368,879 Reeves Feb. 6, 1945 2,446,154 Haven July 27, 1948 2,483,165 Young Sept. 27, 1949 

